Abstract: A solid state imaging device (FIG. 2) includes an array 10 of photoelectric elements 11 on which an image is formed, and overcomes poor resolution due to insensitive areas 12 between elements by interposing between a focussing lens 13 and the array an optically transmissive member in the form of a rotatable disc 15 having parallel faced portions of different thickness 16, 17 which extend into the optical axis of the focussing means in turn and are inclined thereto to displace the image laterally on the array. The difference in thickness causes an image displacement equal to half of the element pitch and signals of each image displacement are stored in frame stores 21, 22 from which they may be read to provide the equivalent of a higher density array. Disc portions may be the same thickness but of different refractive indices or angles to the optical axis. A larger number of portions (FIG. 5) may be used to give more displacements.